Kessler is the leader of the Legion, a role that he took over from Nero when Nero retired in 188 A.F. He was created to be the future Imperial Commander and has made the family proud with what he has done with the Legion.

Kessler is what would be easily described as half brute chimera, half intelligence. He is burly and strong but since he is also an intelligence chimera he doesn't suffer from 'brute chimera syndrome' aka acting like happy-go-lucky cheerful sociopathic idiots (and we love them all the same). Kessler is a military genius and he knows how smart he is and, unlike a lot of his brothers, is secure in his place inside of the Dekker family.

Though Kessler Dekker does have one weakness, a weakness that Silas deliberately injected into him: his family. When Kessler took over the Legion from Nero the Legion took off like a rocket. Every member of the Legion respected Kessler to no limits and would die for their commander.

And Silas didn't like this.

Uneasy with the fact that a young chimera had the entire greywaste army at his beck and call, Silas devised a way to control Kessler: he let him marry, and make immortal, his long time lover, and gave him two chimera children to raise as his own. Not just surrogacy-raised, his sons Caligula and Timothy call Kessler and Tiberius 'Father' and their father/son relationship is as normal as normal can be (aka, they don't have sex, and any family gatherings that include that activity will have either the fathers or Caligula slinking off - no one wants to see their dads do those sort of things). Though the family wasn't pleased with what they saw as blatant favouring, through certain events that warranted Silas using Caligula, Tiberius, and Timothy against Kessler, it soon became obvious just why Silas had allowed Kessler those privileges.

Kessler married Tiberius in 205 A.F when he was 39. Kessler is also one of the only immortal chimeras to be made immortal when he was at an older age. Kessler was made immortal at 37 years old and his husband at 32. He lives in Cardinalhall most of the time with his husband and sons, but also has a mansion in Skyland. Kessler has two german shepards named Dutch and Chief, a serval named Filo, an ocelot named Slater, and many stray cats which roam Cardinalhall. Kessler and Tiberius also have two sengils named Keegan and Aiden and a cicaro named Tarren.